Litospheric plates move as a result of forces resulting from which of the following

Lithospheric plates are part of a planetary scale thermal convection system. The energy source for plate tectonics is Earth’s internal heat while the forces moving the plates are the “ridge push” and “slab pull” gravity forces. It was once thought that mantle convection could drive plate motions.

Explanation:

early settlements on the subcontinent. both the indus and the ganges rivers carried rich silt from the mountains to the plains. when the rivers flooded, the silt spread over the plains and made the soil in the river valleys fertile for farming.

can you explain a little further maybe give multiple choice? ?